DM336P Davicom Semiconductor Incorporated, DM336P Datasheet - Page 14

• Manufacturer Part Number: DM336P
• Manufacturer: Davicom Semiconductor Incorporated

5. Plug and Play (PnP) Module
a. Auto-configuration Ports
Three 8-bit I/O ports are defined for the PnP
read/write operations. They are called Auto-
configuration ports as listed below.
To access the Plug and Play Register, a host should
follow this procedure: Write a target register address
(Register Index), choose a port (WRITE_DATA or
READ_DATA), then enter data. But Plug & Play
Register could be directly accessed without the need
(1) Card Control Registers
14
ADDRESS
Index
WRITE_
00H
01H
02H
03H
04H
05H
06H
READ_
DATA
DATA
Port
Card Select Number
Set RD_DATA port
Resource Data
Serial Isolation
Config Control
Type
Wake [CSN]
W
W
R
Status
(CSN)
Name
0279H
(Printer status port)
0A79H
(Printer status port + 0800H)
Relocatable in range
0203H to 03FFH
Type
Location
R/W A write to this register sets a card CSN. After a serial identification
V.34 Integrated Data/ Fax/Voice/Speakerphone Modem Device Set
W
W
W
R
R
R
A read from this register reads the next byte of resource data. The Status
Register must be polled until bit[0] is set before this register may be read.
Bit [0], when set, indicates it is ready to read the next data byte from the
Resource Data Register.
process, the CSN value (CSN) is uniquely assigned to each ISA PnP card
so that each card may be individually selected during a Wake[CSN]
command.
The location of the READ_DATA port is determined by writing to this
register. Bits [7:0] become ISA I/O read port address bits [9:2]. Address
bits [1:0] of the READ_DATA port are always 1.
A read to this register causes a PnP card in the Isolation state to compare
one bit of the card serial ID. This process is described in more detail in the
next section.
Bit [0] - Reset Command Setting
This bit will reset all logical devices and restore configuration registers to
their power-up values. The CSN is preserved.
Bit [1] - Wait for Key Command Setting
This bit makes the PnP card return to the Wait for Key state. The CSN is
preserved.
Bit [2] - PnP Reset CSN Command Setting
This bit will reset the card CSN to 0. Note that the hardware will
automatically clear the bits without any need for software to clear them.
A write to this register will cause all cards that have a CSN that matches
the write data [7:0] to go from the Sleep state to either the 1) Isolation
state if the write data for this command is zero, or 2) Configuration state if
the write data is not zero.
to write to the ADDRESS port before each access.
The ADDESS port is also the write destination of the
initiation key, which will be described later.
b.
The Plug and Play Registers may be divided into
Card Registers and Logical Device Registers.
According to the Plug & Play specification, if a PnP
card contains more than one logical device, there are
one more copies of Logical Device Registers in the
PnP card. However, the DM6383A contains only one
logical device, the Card Register and Logical Device
Registers are unique for each card. Those PnP
registers or bits not defined below are all read with
value = 0.
Plug and Play Registers
Definition
Version: DM336P-DS-F02
DM336P
August 15, 2000
Final